Hi,
Just to add to all of the above.
CMV is cytomegalovirus, it sometimes presents a bit like glandular fever with a sore throat, swollen glands and a fever. It isn't highly contagious and as is the case with all of the above illnesses most adults have had these illnesses and are therefore protected. (therefore protecting your unborn baby)

Parvovirus is commonly found in the form of the childhood illness called 'slap cheek'. The child has a red rash on the face that looks like it has been slapped. The illness is mild in children just making them grumpy and possibly feverish. This illness often is passed off as a bit of a cold. If your child does have 'slap cheek' it should be kept away from pregnant women.

Varicella is chicken pox, again most adults have immunity to this.

Your doctor rightly was checking for your immunity as all of these illnesses have the potential to affect an unborn child particularly in the first trimester. Having said that though, I believe that the stats say that 85-95 percent of the adult population have immunity. So, it is likely you are already immune.

Often doctors now will also check for Toxoplasmosis immunity a disease that is usually contracted from cat faeces. It also can be found in raw meat, which is why pregnant women are advised to use gloves when handling raw meat and to wear gloves when digging in the garden (the favorite 'loo' for cats!). Toxo can also be contracted from kangaroo meat so women should exercise caution when handling raw dog food (often contains kangaroo) that has the potential to carry this parasite. Toxo is more difficult to contract, however it is always important to be cautious. Many women who have had a lifelong relationship with cats have immunity, but some don't (me!)
Hope this has helped,
Deb